If you are not familiar with electric shavers, here are some basic knowledge. The electric shaver was first invented in America in the 1920s. Since then, they have gradually evolved into more convenience and comfort. Now there are many different types to choose from, which can be controlled by battery or plug-in power supply. The latest electric shaver on the market uses rechargeable power supply, which can be used continuously for more than 1 hour. From a technical point of view, there are two types of electric shavers: "foil" and "rotary". The rotary type uses a rotating blade, while the foil type uses an oscillating blade. Because they are designed according to ergonomics, both types are good choices. Rotary noise is less and cleaner. These two kinds of razors can give people different feelings. However, we should know that the electric shaver can only be used for dry shaving, and shaving foam and water cannot be used in most cases. Blades can be cleaned, and some of them even have self-cleaning facilities. The electric shaver is no closer to the skin than the cartridge shaver. This is because of the need to ensure speed and safety. This kind of razor is more suitable for people with fast beard growth.